The present invention relates to a method and apparatus for processing seed cotton. More particularly, the present invention relates to a method and apparatus for recovering a fiber fraction from seed cotton.
Various arrangements for delinting or ginning cotton have been proposed. Such devices have included saw ginners which tend to tear or pull at the seed cotton to remove lint therefrom. It is often desirable to remove a long fiber fraction from the cotton seed separately from the remaining short fiber fraction. Such a division of fiber fractions is desirable depending upon the intended use of the lint and is not satisfactorily accomplished by the known devices. It is also desirable to remove a long fiber fraction without tearing or breaking a substantial portion of the long fibers. Accordingly, there has been a need within the cotton industry for a more effective method and apparatus for obtaining a long fiber fraction from the seed cotton.
One proposed device included a large, rotatable circular cage comprised of a plurality of smaller rollers arranged parallel to one another along the periphery of the large cage. At least one nip roll was arranged in contact with the outer periphery of the rollers of the cage. The cage was enclosed within a housing from which the air was constantly withdrawn. The seed cotton was fed to the inside of the cage and was picked up by the plurality of rollers which attempted to carry the seed cotton upwardly to the location of the nip roll. The apparatus proved to be ineffective for several reasons. In particular, the seed cotton did not tend to remain in contact with the rollers and a "snow storm" ensued within the cage. Such random movement of the seed cotton produced a substantially lower yield than anticipated and necessitated frequent stopping of the machine to clear the inside of the cage. One theory set forth for explaining the onset of the "snow storm" effect was that the air flow was turbulent throughout the cage roll and consequently the seed cotton was merely blown around within the cage roll.
In a further proposal, a nip roll was placed in contact with the inner periphery of the cage roller and solid shrouds were placed closely adjacent the outside periphery of the cage roll in the area surrounding the nip roll in an attempt to maintain the seed cotton properly in position on the outside of the rollers. With this arrangement, turbulence was apparently created under the shrouds which tubulence cause a portion of the long fiber fraction to be "blown" outwardly. Consequently, the long fiber fraction could not be removed by the nip roll and the yield obtained was unacceptably small.
It is an object of the present invention to provide an effective method and apparatus for removing substantially all of a fiber fraction of a predetermined length contained within seed cotton.
It is a further object of the present invention to remove a fiber fraction from seed cotton with a method and apparatus which are capable of processing large quantities of seed cotton in an expeditious manner.
Still a further object of the present invention is to provide a method and apparatus which remove a quantity of trash from the seed cotton prior to removing the fiber fraction and maintain the trash separate from the recovered fiber fraction.
These objects and others are accomplished by a method and apparatus according to the present invention. The apparatus includes a plurality of closely spaced substantially parallel rollers with each of the rollers being freely rotatable about its axis. An arrangement for driving the plurality of rollers in a continuous path substantially perpendicular to the axes of the rollers is also provided. Seed cotton is deposited on a first side of the path and at least one relatively large diameter nip roll is arranged in abutting engagement with a second side of the continuous path opposite the first side. A suction source for drawing air from the first side to the second side of the continuous path of the rollers is also provided for aiding in extending a portion of the fiber fraction between adjacent ones of the rollers. The suction source draws a substantially constant quantity of air substantially straight between the rollers in an area at least immediately upstream of the nip roll relative to the direction of movement of the continuous path. The nip roll is driven about its axis for separating the fiber fraction extended between the rollers by the suction source from the seed.
In a further embodiment of the present invention, a brush is arranged on the second side of the continuous path generally opposite to the location where the seed cotton is deposited. The brush is adapted to extend and align the fiber fraction between adjacent ones of the plurality of rollers to facilitate separation of the fiber fraction from the seed by the nip roll. In the preferred embodiment, the brush and the nip roll are adjustable relative to the continuous path in order to change the pressure therebetween and vary the quantity of fiber fraction removed Further, the brush is adapted to remove trash from the seed cotton. An arrangement is provided for ensuring that the trash removed remains separated from the fiber fraction removed by the nip roll.
Further, according to the present invention, a second nip roll is arranged downstream from the first nip roll on the second side of the continuous path. A device for agitating the seed cotton on the first side of the continuous path after removing the portion of the fiber fraction with the first nip roll is also provided. In a first embodiment, the device for agitating the seed cotton includes a rotatable roller frictionally engaging an edge of the continuous path of the rollers to thereby cause rotation of the rollers to agitate the seed cotton. In a second embodiment, the device for agitating the seed cotton includes a rotatable roller having a plurality of bristle-like projections adapted to engage the seed cotton and agitate the same.
A method for recovering a fiber fraction according to the present invention includes driving a plurality of spaced apart parallel rollers along a continuous path. Seed cotton is deposited on a first side of the continuous path and a substantially constant quantity of air is drawn substantially straight between the rollers from the first side to a second side of the continuous path to draw a portion of the fiber fraction between adjacent ones of the rollers. The fiber fraction is separated from the seed cotton by nipping the fiber fraction between the rollers and at least one rotatable nip roll arranged on the second side of the continuous path. In a further aspect of the method according to the present invention the fiber fraction is extended and aligned between adjacent ones of the rollers with a rotatable brush arranged on a second side of the continuous paths.